Restructuring Charges (Schedule Of Accrued Restructuring Balances) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 3,956
Restructuring charges	7,312
Cash Payment	(4,464)
Non-Cash Activity	(2,090)
Foreign Exchange Adjustments	0
Ending Balance	4,714
2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	4,707
Cash Payment	(1,357)
Non-Cash Activity	(145)
Foreign Exchange Adjustments	0
Ending Balance	3,205
2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3,956
Restructuring charges	2,605
Cash Payment	(3,107)
Non-Cash Activity	(1,945)
Foreign Exchange Adjustments	0
Ending Balance	1,509
Severance [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	4,486
Cash Payment	(1,317)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	3,169
Severance [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3,956
Restructuring charges	(1,183)
Cash Payment	(2,013)
Non-Cash Activity	(72)
Foreign Exchange Adjustments	0
Ending Balance	688
Leased facilities and equipment [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	148
Cash Payment	0
Non-Cash Activity	(145)
Foreign Exchange Adjustments	0
Ending Balance	3
Leased facilities and equipment [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	2,550
Cash Payment	(843)
Non-Cash Activity	(1,144)
Foreign Exchange Adjustments	0
Ending Balance	563
Other Exit Costs [Member] \| 2020 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	73
Cash Payment	(40)
Non-Cash Activity	0
Foreign Exchange Adjustments	0
Ending Balance	33
Other Exit Costs [Member] \| 2019 [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance	0
Restructuring charges	1,238
Cash Payment	(251)
Non-Cash Activity	(729)
Foreign Exchange Adjustments	0
Ending Balance	$ 258

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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